Former South Africa leader FW de Klerk, singers Dame Shirley Basseyand Katherine Jenkins, composer Lord Lloyd Webber and wife Madeleine and Lord Jeffrey Archer with wife Mary will also be in the congregation.

Former Republican congressman Newt Gingrich, actor Michael Crawford - most famous for his roles in Some Mothers Do 'Ave 'Em and Phantom of the Opera, and Sir Tim Berners-Lee, inventor of the world wide web have accepted their invitations.

Singers Dame Vera Lynn and Elaine Paige, actors Sir Michael Caine and Robert Hardy and veteran wildlife broadcaster Sir David Attenborough will all be at St Paul's.

All surviving former US Presidents - Jimmy Carter, George Bush, Bill Clinton and George W. Bush - a Reagan family representative, and former US Secretary of State Hillary Clinton were invited to the event. But President Barack Obama announced a Presidential delegation would be sent led by George Shultz and James Baker III, Secretaries of State from the Thatcher era. Also part of the delegation are Barbara Stephenson, Charge d'Affaires at the US Embassy in London, and Louis Susman, former American Ambassador to the UK and Northern Ireland. Former US vice-president Dick Cheney and ex-secretary of state Henry Kissinger will also be there but not as part of the delegation.

Ten members of staff from the Ritz hotel, where Lady Thatcher died on Monday, have also been invited to her funeral as thanks for the care she received. The 87-year-old had been staying at the five-star hotel since Christmas.

Family, friends and colleagues will also be at the ceremonial service, which will take place with full military honours.

Other confirmed attendees include:

Michael Portillo and his wife Carolyn

Lord Charles Powell, Lady Thatcher's former private secretary

Lord Carrington, Margaret Thatcher's first Foreign Secretary and later head of NATO

Canadian Prime Minister Stephen Harper

Former Canadian Prime Minister Brian Mulrooney, who was in office from 1984 to 1993

Former Australian Prime Minister John Howard, and wife Janette, representing Australia

Lord and Lady Harris of Peckham. Lord Harris is a Tory donor and chairman of Carpetright.

Lord Maurice Saatchi. Saatchi & Saatchi was the advertising firm behind the famous 'Labour isn't working' poster used in the 1979 election campaign which saw Margaret Thatcher become Prime Minister

Businessman Gerald Ronson, who was jailed for his part in the Guinness shares scandal

Sir Bernard Ingham, chief press secretary to Margaret Thatcher during her years as Prime Minister, and his wife

Director of The British Forces Foundation Mark Cann

Archbishop of York Most Rev John Sentamu

Two-time US presidential candidate Ross Perot

Military guests including: General Sir David Richards, Field Marshal Lord Bramall, Marshal of the Royal Air Force Lord Craig of Radley, General Sir Peter Wall, Field Marshal Sir John Chapple, Air Chief Marshal Sir Stephen Dalton, Air Chief Marshal Sir Stuart Peach, Major General Ed Davis and General Sir Michael Jackson

Invitations will be sent out on Friday 12 April. The white VIP invitations will see guests seated under the Cathedral's famous dome. A red or green stripe will show whether they are to sit on the port or starboard side. Other invitations are colour-coded relating to where guests are to be seated in the cathedral.

Guests at the funeral will be asked to wear full day ceremonial dress without swords, morning dress with a black waistcoat and black tie or dark suit, day dress with hat. Medals and decorations may be worn.

A spokeswoman said: "Those invited include family and friends of Lady Thatcher, those who worked with her over the years, including all surviving members of her Cabinets, former Chiefs of Staff, Conservative associates, peers and MPs, members of the Cabinet, peers and MPs, members of the Order of the Garter, members of the Order of Merit, foreign associates and dignitaries and representatives from the wide range of groups she was associated with.

"In agreement with Lady Thatcher's representatives, around 200 states, territories and international organisations are being invited to send an official representative to the funeral service.

"We have invited those countries and institutions with whom we have normal diplomatic relations. In addition, there are invitations being made in a personal capacity to some current and former world leaders as well as others from overseas who had a close connection to Baroness Thatcher."